While there are still about two months until the midterm elections, it seems more and more likely that there will be large Republican gains in Congress. The latest Gallup tracking poll gives Republicans a 10-point lead in party preferences, the party’s highest margin in the poll’s history. Right now, the Intrade betting market indicates a 77 percent probability of a Republican takeover of the House and the Politico website is reporting increasing despair among Democrats of retaining key swing seats. Even in the Senate, where Democrats presently enjoy a comfortable majority, recent polling indicates that Republicans are poised to make major inroads, with some possibility of outright GOP control.

But an important question, which has both political and governing implications, is what the Republicans plan to do with a majority in the House and maybe the Senate.

Democrats, faced with a difficult electoral environment, are largely arguing that a return to Republican rule in Congress would simply mean restoration of “failed” Republican policy under President George W. Bush. In a colorful analogy, President Obama compared Republicans to a driver that just put the car into a ditch and now wants the keys back.

While it seems unlikely that voters are going to buy into this turn back the clock argument completely, Republicans do need to give voters some idea of their plans. Indeed, the greatest Republican triumph of recent years in Congressional elections, the 1994 blowout, was preceded by the Contract With America, a pledge by GOP candidates to support eight governmental reforms and to bring ten bills to a vote. So far there has no similar GOP statement of principles.

In a recent speech in Cleveland, House minority leader (and quite possibly the next speaker) John Boehner did help to clear up a few of the questions about what Republican rule would mean. As recounted by economist Larry Kudlow, Mr. Boehner, in addition to advocating the extension of all Bush tax cuts (including for high earners), called for repeal of the new revenue provision of the health care bill that would require small business to issue 1099 paperwork for purchases over $600, a rollback of all non-defense discretionary spending to 2008 levels, the end of all TARP bailouts and a freeze of all federal salaries.

Mr. Kudlow reports that the Republicans are likely to bring out a more expansive statement of principles in the next few weeks. This is just as well because Mr. Boehner’s proposals are somewhat limited and more global ideas are likely needed. For example, to spur job growth the Republicans might propose a payroll tax holiday (a temporary moratorium on employer and employee FICA contributions), paid for by major cuts in government bureaucracy. As an antidote to the very unpopular health care bill, the GOP could consider a pledge not to appropriate any funds implementing the new legislation. The GOP might also consider at least some of the sweeping tax and budget long-term proposals advocated by Representative Paul Ryan in his Roadmap.

At a minimum, Americans are seriously thinking about returning Republicans to power in one or both houses on Capitol Hill. Because it is both good politics and the right thing to do, the GOP owes it to the electorate to be more specific as to its principles and proposals.